'COP WITHOUT A BADGE'Beverly Merrill, before she became Danielle Staub, one of the 'Real Houswives of New Jersey'

"Real Housewives of New Jersey" star Danielle Staub's ex-husband Kevin Maher "flipped out" when he discovered this week that Staub, whom he knew as cocaine-lovin' stripper Beverly Merrill, had become a reality star whose unsavory past was about to be revealed on national television, according to one of Maher's friends, a former investigator with the Manhattan District Attorney's Office.

Maher, a felon-turned-informant who worked with law enforcement agencies in New York and New Jersey in the 1980s, is the subject of Charles Kipps' book, "Cop Without a Badge." The book details Maher's relationship with Merrill, an exotic dancer who claimed she'd bedded a thousand men, and includes a mugshot of Merrill after she had been busted for extortion, kidnapping and drug possession.

Jim Doherty, now a retired investigator, met Maher in the 1970s, after Maher got in trouble with the law (again). Doherty helped him get paroled, and Maher later went to work for Doherty as an informant. The two men still talk nearly every day. In fact, Doherty's daughters tipped him that the promo for next week's "Real Housewives" would feature the book, so Doherty alerted Maher. "He's bouncing off the walls," Doherty says. "He's a Type-A personality."

Doherty says that Maher "doesn't have any bad feelings" about Merrill, who later changed her stripper name to Danielle and whom Maher last saw gyrating at Shakers in Carlstadt in 1992. Doherty never met Merrill, though he did catch a rerun of the "Real Housewives" episode Wednesday night. "Just the ending. I don't want to sit through the whole thing."

Meanwhile, retired Carlstadt detective Robert Colaneri, also featured in the book, confirmed that Merrill is in fact Danielle Staub. "I spoke with her one time, only because I think she was dancing in Shakers, and Kevin had gone in there. After she saw Kevin and was nervous, she called up the police department ... I think that was the last contact."

Both Colaneri and Doherty says Kipps wants to try to get the out-of-print book back into circulation as a paperback.

"What a great summer read it would be," Colaneri says. "With this kind of publicity, it might be the push it needs." Or you could just pick up a copy on eBay. Minimum price: $61 and climbing.